1. Field of the Invention
The present invention relates to a mobile communication system.
2. Description of the Related Art
In the 3GPP (3rd Generation Partnership Project), LTE (Long Term Evolution) and SAE (System Architecture Evolution) have been studied. One of the important issues in that study is QoS (Quality of Service).
In studying QoS control for the entire SAE architecture of SAE/LTE mobile communication system including LTE network and SAE core network, communication over the SAE core network between a visited side and a home side needs to be taken into consideration. The communication over SAE core network is typically a roaming communication over global roaming exchange (GRX) of GSMA between VPLMN (Visited Public Land Mobile Network) at the visited side and HPLMN (Home PLMN) at the home side.
As of now, in studying QoS control of the SAE/LTE mobile communication system, QoS control of LTE network corresponding to the radio access network is focused on, but QoS of SAE core network has not been studied so much. Therefore, it is required to establish QoS control for covering over the SAE architecture including the SAE core network.
Generally, VPLMN and HPLMN are operated by different operators and a policy of each operator is applied to each PLMN, thus, the policy to be applied to the user of HPLMN and the policy to be applied to the user of VPLMN may differ from each other.
The policy of VPLMN is defined by V-PCRF (Policy and Charging Rules Function) and the policy of HPLMN is defined by V-PCRF. PCEF (V-PCEF: Policy and Charging Enforcement Function) of VPLMN complies with the policy defined by V-PCRF and PCEF of HPLMN (H-PCEF) complies with the policy defined by H-PCRF.
The end-to-end service goes over SAE core network between V-PCEF and H-PCEF. On SAE core network, a SAE CN Bearer is established between UPE (User Plane Entity), which is V-PCEF, or V-IASA (IETF Administrative Support Activity)) and IASA, which is H-PCEF, (or H-IASA). QoS control for covering the entire SAE architecture including the SAE CN Bearer is required.
The Japanese Patent Laid-Open No. 2003-298616 disclosed an example of QoS control in a mobile communication system for providing the end-to-end service by connecting two nodes (a visiting node and a control gate node) by a core network. According to that, QoS control for covering the end-to-end service become available.
The SAE/LTE mobile communication system that is studied by 3GPP adopts the SAE architecture with higher flexibility in setting or changing a policy. The control disclosed in the Japanese Patent Laid-Open No. 2003-298616, however, does not take into consideration of the system configuration of the SAE/LTE mobile communication system. Therefore, it cannot be applied easily as it is.